package com.lxb.myforum.security;

import java.util.Collection;
import java.util.Iterator;

import org.apache.commons.lang3.StringUtils;
import org.springframework.security.access.AccessDecisionManager;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.access.SecurityConfig;
import org.springframework.security.authentication.InsufficientAuthenticationException;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.stereotype.Component;

/**
 * 
 * @author lxb
 *
 */
@Component("myAccessDecisionManager")
public class CustomAccessDecisionManager implements AccessDecisionManager {

	@Override
	public void decide(Authentication authentication, Object object, Collection<ConfigAttribute> configAttributes)
			throws AccessDeniedException, InsufficientAuthenticationException {
		if (configAttributes == null) {
			return;
		}

		// 所请求的资源拥有的权限(一个资源对多个权限)

		for (ConfigAttribute ca : configAttributes) {
			// 访问所请求资源所需要的权限
			String needRole = ca.getAttribute();
			System.out.println("Need Roles: [" + needRole + "]");
			// ga 为用户所被赋予的权限。 needRole 为访问相应的资源应该具有的权限。
			// authentication.getAuthorities() 用户所拥有的权限
			for (GrantedAuthority ga : authentication.getAuthorities()) {
				System.out.println("Have Roles: [" + ga.getAuthority() + "]");
				if (StringUtils.equalsIgnoreCase(needRole.trim(), ga.getAuthority().trim())) {
					System.out.println("OK==有权限");
					return;
				}
			}
		}
		// 没有权限
		throw new AccessDeniedException("没有权限访问！");
	}

	@Override
	public boolean supports(ConfigAttribute attribute) {
		return true;
	}

	@Override
	public boolean supports(Class<?> clazz) {
		return true;
	}
}
